Labidodemas semperianum Selenka, 1867

Setyastuti, Ana, Solis-Marin, Francisco Alonso & Lüter, Carsten, 2024, Sea cucumbers of the genus Labidodemas (Holothuroidea: Holothuriida: Holothuriidae) from Indonesia, with the description of a new species and a revised key to the genus, Zootaxa 5506 (2), pp. 227-244 : 232-235

publication ID	https://doi.org/ 10.11646/zootaxa.5506.2.4
publication LSID	lsid:zoobank.org:pub:55527A8F-3454-49A2-AD65-ECBAE234C03D
DOI	https://doi.org/10.5281/zenodo.13746666
persistent identifier	https://treatment.plazi.org/id/03C0F828-FFB2-3A12-95F4-FB78FCB83308
treatment provided by	Plazi
scientific name	Labidodemas semperianum Selenka, 1867
status

Treatment

Labidodemas semperianum Selenka, 1867 View in CoL

( Figures 5–8 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 )

Labidodemas semperianum Selenka, 1867: 309 View in CoL , pl. 17, figs. 1–3; Massin et al., 2004: 1833, figs. 9A–J, 10A–H, map 6 (synonymy and records 1970–2003).

Type material. Lectotype MCZ 736 (the dissected specimen, 75 mm long), paralectotype MCZ 736 (the nondissected specimen, 90 mm long) ( Massin et al. 2004). The Syntype ZMG (no number given by Selenka, 1867) are untraceable ( Massin et al. 2004).

Type locality. Formerly Hawaiian Islands (as Sandwich Islands), but now Society Islands according to the designation of lectotype ( Massin et al. 2004) .

Material examined. MZB Hol.385 (one specimen), 68x 19 mm in ethanol, collected in Batulawang, Situbondo, Jawa Timur, by diving, found under a rock, 5 m depth, coll. by Tim Teripang LIPI 2018 .

External description. Body cylindrical; colour in ethanol white uniformly ( Figs. 5A, B View FIGURE 5 ). Body soft to the touch, 1–2 mm thick. Mouth and anus terminal; mouth brown, surrounded by 16 potato-digitate tentacles. Anal papillae present, not calcified. Dorsal papillae small, conical shape, yellow, scattered over the surface. Ventral tube feet are very long (3 mm), white to yellowish, arranged in three rows in the ambulacral areas with a zigzag pattern.

Internal description. Calcareous ring small ( Fig. 5C View FIGURE 5 ), with radial pieces twice wider than interradial pieces (2 mm wide and 2 mm high). Cuvierian tubules present, not expelled during collection, adhesive, bulbous and thick, brownish, branched, distal part of the tube with spherules, more than 10 attachment sites. Tentacle ampullae present, short. Single Polian vesicle, sac-like. Stone canal not observed. Gonad one tuft, branched. Respiratory trees arise from a single stalk. Longitudinal muscles flat and completely attached to the body wall. Inner body wall whitish, intestine filled with gravel and coral rubble.

Ossicles. Dorsal body wall with tables and buttons; tables disc 60–80 µm across, disc rims mostly spinous, perforated by 4–6 central holes; table spire low (20–30 µm), ending in four to six long spines, some of them bifurcated distally; table crown generally larger than table disc ( Fig. 6A View FIGURE 6 ). Pseudo-buttons only a few; 60–80 µm long; knobbed ( Fig. 6B View FIGURE 6 ). Ventral body wall holds tables and buttons ( Figs. 6C, D View FIGURE 6 ) similar to those in dorsal body wall.

Dorsal papillae with tables, buttons, pseudo-buttons, rods and plates; tables disc 55–90 µm across, disc rims spinous; perforated by four to five central holes and a variable number of peripheral holes; spire low, single crossbeam, ending in four to six long spines with distal bifurcation; table crown wider than table disc ( Fig. 7A View FIGURE 7 ). Buttons 40–50 µm long, sometimes with knobbed; pseudo-buttons 60–100 µm long; rods 50–90 µm long ( Fig. 7B View FIGURE 7 ); small plate observed in heaps with rods and buttons, 100 µm across ( Fig. 7C View FIGURE 7 ). Ventral tube feet only with tables and large end plates. Tables 60–80 µm across, with four to five central holes, crown sometimes with only three spines, tables reduced to the (spiny) disc or with a reduced crown also observed ( Fig. 7D View FIGURE 7 ). Endplate reaching 500 µm across ( Fig. 7E View FIGURE 7 ).

Tentacles with only rods, thin, smooth or spiny, 30–60 µm long ( Fig. 8A View FIGURE 8 ). Ossicles of anal papillae consist of a mixture of table discs, 40–50 µm across, irregular rods and reduced buttons, 30–45 µm long ( Fig. 8B View FIGURE 8 ).

Remarks. The specimen examined in the present study possesses Cuvierian tubules with more than 10 attachment sites. Such had never been observed before in this species. On the other hand, L. semperianum in the present study has few buttons and pseudo-buttons in the body wall and dorsal papillae, similar to the study of Massin et al. (2004).

Ecology. Found in shallow waters, less than 30 m depth ( Lane et al. 2000), under coral rocks.

Depth range. 1–30 m depth.

Geographic distribution. The following new locality is added here since Massin et al. (2004: 1835, map 6) publication: Situbondo-East Java, Indonesia (present study).